The UNESCO-ISARM (International Shared Aquifer Resources Management) Initiative conducted a global inventory of transboundary aquifers identifying more than 273 systems in the world (Atlas of Transboundary Aquifers, 2009). Very few of these systems have developed a common management structure among the riparian countries; moreover, a little number of aquifers is jointly managed with surface waters, despite this being a key principle of Integrated Water Resources Management (IWRM). To ensure an efficient management of aquifers shared by several countries it is crucial to initiate cooperation between the parties and establish the necessary mechanisms to enable such cooperation.

The UN General Assembly (UNGA) adopted the Resolution (A/RES/63/124) on the “Law of Transboundary Aquifers” in December 2008. Through this resolution the UNGA encourages aquifer states to make appropriate bilateral or regional arrangements for the proper management of their transboundary aquifers, taking into account the provisions contained in the annexed Draft Articles. The Draft Articles on the “Law of Transboundary Aquifers” were prepared by the United Nations International Law Commission (UNILC) with the technical support of UNESCO-IHP. The Resolution provides a framework to promote cooperation amongst states in the management and development of transboundary aquifers.

While numerous agreements refer to transboundary surface waters, very few specifically address transboundary aquifers. To date there are only four transboundary aquifers that are covered by legal frameworks (agreements and ministerial declaration): Genovese aquifer, Guarani Aquifer, Nubian Sandstone Aquifer System, North Western Sahara Aquifer System. Of particular importance is the case of the agreement of the Guarani Aquifer (signed by four countries: Argentina, Brazil, Uruguay and Paraguay) which makes explicit reference to the Draft Articles on the “Law of Transboundary Aquifers” and follows the recommendations contained in the UNGA Resolution 63/124.

Given the critical importance of groundwater resources for drinking water supply and agricultural uses in many countries, appropriate legal frameworks should be developed to support the sustainable management and governance of these resources.

A series of case studies, based on existing inventories, will be collected to showcase best practices and concrete examples of sustainable transboundary aquifers management. Moreover, through the milestones identified in the Target Action Plan, the “Target and Solutions Group” will mobilize their respective networks in all countries to convey guidelines and recommendations contained in the UNGA Resolution 63/124 and will closely monitor the achievements made by countries in implementing cooperation mechanisms.